Die cushion



D. STRAIN E! DIE CUSHION Feb, 12 1924. m mm Filed April 11, 1818 YJILUMTST Pf h nted Feb. 2,, 1924.

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nav'rn s rewn, "or cnrcneo, ILLINOIS, Assmnon, BY mnsnn ASSIGNIENTS, 'romnaumrn TOOL a mnumcrunma comrmr, or CHICAGO, ILLmoIs, a com ronarron orILLINOIS.

DIE CUSHION.

Application filed. April 11, 1918. Serial No. 227,940.

' To all whom it may mm.-

Be-it known that I, Davin STRAND, a citi zen of the UnitedStates-residing at Chica 0, in the county of Cook and State of I] mois,have nvented certain newand usei'ul Improvements in Dle Cushions, ofwhich the following is'a specification.

Iii-large used -for stamping or -This invention relates to improvementsin die cushions particularly of the fluid pressure type. Y

sheet metal presses, such as are shaping automobile bodies or work ofequally large dimensions,

heretofore the means usually, employed for exerting a pressure on thegripper plate of the die were coil s rings, such as are used on railroadcars. W0 or more lengths of these springs are placed one under the otherand sometimes as many a twenty or thirty springs on one die areemployed. It is evident that'it is mechanically impossible to tightenthese springs so that they will all exert-the same pressure at all ointsupon the gripping means to which t ey are attached, because of thedifferent temper in the steel and by reason of other mechanicalimperfections. Furthermore, phere is no way of determining the pressureexerted on the gripping means when the spring is ti htened.-

P0 overcome these difliculties and objections fluidpressure cushions areemploye instead of the springs and it is possible to control thepressure mechanically and positively. A further advantage of thisinvention is that once" the pressure necessary on the die is determined,all experimenting as to the pressure such. as is always necessa in theemployment of springs is eliminate because the same pressure canmechanically, easily and ositively be repeated which saves considerab etime and experiment in setting up the die.

A further object of in the application of the invention consists aplurality of fluid pressure cush'ons in a single machine, and meanswhereb the cushions may be sup- '-plied with a uid preferably from acommo'n source'of supply adapted to flow from and back to the sourcedurmg' the operation of the cushlons.

To the attainment of these ends and the accom lishment of the; other newand usetul ob]ects as "will appear,'the invention consists in thefeatures of novelty in substanwill apply eq and which fluid is ,suitableconstruction and is connected pre is a guide more fully described andclaimed and shown in. the accompanying drawing, illustrating thisinvention and in which;

- Figure 1 is'a view artly in vertical section and partly in si eelevation of a portion of a die press having die cushions constructedin'accordance with the principles of this invention applied thereto.

Figure 2 is a diagrammatic view showing one method of,introducing afluid into the cushions.

' Referring more particularly to the drawing, the numeral 10 designatesgenerally a bolster plate supported upon a suitable structure and uponwhich plate a male die member 11 is adapted to be secured and which diemay be of any. desired size and configuration. (lo-operating with themale member 11 is a fema e die member 12, which is given a reciprocatingmovement in amand a pin p ate 16 and in order to prevent the pins 15from becoming disengaged from the bolster plate 10, when the pin p ate16 passes out of engagement with the ends of the pins, the pins may beprovided with heads 17 adapted to enter sockets 18 in the bolster plate.

A plurality of fluid ressure cushions are connected with the madliine soas to control the operation of the pressure plate, and as theconstruction and operation of each of the cushions is the same, thedescription of one ually as ,well to them all. The cushion conslstsessentially'of a cylinder 19 of any desired size and configurationwithin which a piston 20 is-adapted to reciprocate and this piston mayalso be of an erably with a tubular extends through .a suita ing 22.Secured to the endof thecylinder piston rod 21 which extend into thetubular portion 22 this guide rod 23 is provided with an inlet Ispacking or bush- 3 rod 23 which is of a length to passage 24 leadingfrom the outside of the cylinder and communicates with dischargeopenings leading into the interior of the cylinder. If desired asuitable bear ng or packing ring 26 may be provided in the tubularpiston 21 and against WhlCh the guide rod 23 has a bearing.

In the present form of the invention, the c linder 19 is supported bmeans of suitable eye 'beams26, upon w ich the cylinder rests and theeye. beams in turn are held in position by means of a suitable washer orcollar 27 through which tie rods or bolts 28 pass and have a threadedextremity 29 upon which a suitable nut 30 is threaded. The other end ofthe tie bolts are secured to any fixed part of the machine.

A bearing block or'element 31 may be connected with the end of thepiston 21 which latter is referably closed by means of a suitable lilg32 to prevent the escape of the fiuid and the bearing block 31 isreferably provided with a reduced portion 3 to form having branches 37leadin a shoulder 34 and which reduced portion 33 is recessed into thepin plate 16 so that the pin plate will rest upon the shoulder 34 to esupported thereby- Thus it will be manifest that when the piston andcylinder are given a relative reciprocating movement, the pin plate 16,togather with the pins 15 and the pressure member 13 will rise or fallaccording to the relative movement of the piston and cylinder. In thepresent form of the invention the fluid is supplied to the cylindersfrom a suitable source such as by means of a pipe 36 therefrom andconnected with some of t e cushions and branches 38 leading from thebranches 37 and connected with others of the die cushions and ifdesired, another pipe connection 39 may lead from the supply pipe 36 tostill another die cushion.

It will thus be manifest that during the relative reciprocating movementof the cylinder and piston, the fluid will flow into and out of thecylinder from and back to pressure will be exerted at all points on thepressure member 13.

It will also be manifest that after the desired pressure has beenobtained, it is not nary to readjust the parts after each operatiomasthey will maintain their con- Stent and unvarymg pure.

Furthermore by the .use of this improved attachment it is possible toconvert an ordinary power punch press into a sheet,

condition for a drawing operation and shows this improved die cushionactive for operation, the ram of the press not being illustrated in thedrawing, it being understood that the die member 12 is connected withthe ram.

The parts located above the bolster plate 10, that is, the elements11,12, and 13, as well as the elements 15, do not constitute a part ofthe press pro er but do constitute parts of the die, and t erefore bythe statement that a punch press may be changed or converted into asheet. metal drawing press, is meant that the drawing die embodying theelements 11, 12, and 13, as well as the pins 15, are to be removed fromthe press and replaced by another die for performing the desiredoperation. At the same time, the pressure is removed fromthe cushion.

It will. thus be seen that the press will then be adapted for thepunching work, or the work for which it was originally desi ned.

at is claimed as new is 1. Means for converting an ordinary power punchress into a sheet metal drawing press whi e maintaing the press in tactfor its original designed purposes, said means embodying a cushion, thesaid cushion embodying a plurality of pressure cushions,

and gripping means for the material carrying pro ect1ng operating andguiding means, a plate enga ed by such projecting means, and with W ichplate the cushions are operatively connected, whereby a substantiallyunvarying pressure will be exerted by the cushions upon the grippingmeans, said cushions and the mechanlsm responsive to the operationthereof being ada ted to be rendered inactive at will, while theremaining parts of the press remain active.

2. Means for converting an ordinary power punch press into a sheet metaldrawing press while maintainin the press in tact for its ori inal desi eurposes, said means embodying a cus ion, the said cushion embodying apluralityof pressure cushions, gripping means for the material carryingprojecting operating and guiding means, a plate enga e by suchprojecting means, and with whic plate the cushions are opera tivelyconnected, whereby a substantially unva ing pressure will be exerted bythe cus ions upon the gri ping means, said cushions and the mac anismresponsive thereto being adapted to be rendered inactive at will whilethe remaining parts of the press remain actiye, -and a common source ofsupply for distributmg the fluid to the cushions.

3. Means for converting an ordinary power punch press into a sheet metaldrawing press while maintaining the press in tact for its originaldesigned purposes, said means embodying a cushion, the said cushionembodying a plurality of fluid pressure cushions, gripping means for thematerial carrying proJecting operating and guiding means, a plateengaged by such projecting means, and with which plate the cushions toare operatively connected, whereby a substantially unvarying pressurewill be exerted by the cushions upon the gripping means, said cushionsand the mechanism responsive to the operation thereof being adapted tobe rendered inactive at will, while the remaining parts of the pressremain active, and a common source of supply for distributing the fluidto the cushions, the said supply embodying means whereby the fluidpressure will be equally distributed to all 25 of the cushions.

In testimony whereof I have signed my name to this specification on this6th day of April, A. D. 1918.

DAVID STRAND.

